Information YOU Need to Know

The Zika virus arrived in the United States this summer, with local transmission reported in and around Miami, FL, and, most recently, suspected cases near Brownsville, TX.

The Zika virus arrived in the United States this summer, with local transmission reported in and around Miami, FL, and, most recently, suspected cases near Brownsville, TX.

The virus causes birth defects in babies born to some infected pregnant women, including microcephaly, where babies are born with underdeveloped heads and brain damage. Zika has also been linked to Guillain-Barre syndrome, a condition in which the immune system attacks the nerves. It’s mainly spread through mosquitoes, although some cases of sexual transmission have been reported.

Groups at high risk

On Dec. 9, the CDC lifted its last Florida travel advisory for pregnant women, for an area of south Miami Beach. However, the CDC advises pregnant women to “consider postponing travel” to areas where local transmission has been reported, including South Florida and Brownsville, TX, near the Mexican border.

In addition, the CDC has issued travel warnings for pregnant women in countries where the disease is spreading.

Transmission

The Zika virus, first identified in Uganda in 1947, is transmitted by Aedes mosquitoes, the same type of mosquito that carries dengue fever, yellow fever, and chikungunya virus. A mosquito bites an infected person and then passes those viruses to other people it bites. Outbreaks did not occur outside of Africa until 2007, when it spread to the South Pacific.

Zika has “never been thought of as a severe infectious disease until now,” says Amesh Adalja, MD, a spokesman for the Infectious Diseases Society of America.

The CDC has confirmed Zika can spread through sex, usually after a person traveled to an area where Zika has broken out, got the virus, and gave the virus to a sex partner who did not travel. Infected women and men can both pass the virus to sex partners -- even if they haven’t shown symptoms of infection, the CDC says. In addition, infected pregnant women can pass the virus on to their fetus. Some studies have also shown the virus can be found in blood, semen, urine, and saliva of infected people, as well as in fluids in the eye.